Macgregor



April 26, 1955 D. Mac Re. 23,985

VALVE CONSTRUCTION Original Filed April 15, 1946 4 Sheetis-Sheet lAlfarntys i w A v 7 .l m ..t w km w 2 /2 an. 1 L a a l a I [IL 7 2 8 Z 43 I I m Fig. I

April 1955 D. M GREGOR Re. 23,985

VALVE CONSTRUCTION Attorneys April 26, 1955 D. MHCGREGOR 23,985

VALVE cous'muc'nou Original Filed April 15, 1946 4 Sheets-Sheet 3Inventor David Macfegor IIJW+WM Affomcys April 26, 1955 D. M eREGoR23,935

VALVE CONSTRUCTION Original Filed April 15,-1946 4 Sheets-Sheet 4Inventor Dav/d Macregar valve body and which necessarily lies in UnitedStates Patent Oflice Re. 23,985 Reissued Apr. 26, 1955 I 23,9ss

VALVE CONSTRUCTION David MacGregor, East Chicago, Ind., r to EdwardValves Incorporated, East Chicago, Ind a corporation of Indiana OriginalNo. 2,621,016, dated December 9, 1952, Serial No. 662,340, April 15,1946. Application for reimue August 2, 1954, set-m No. 441,452

20 Claims. (Cl. 251-50) Matter enclosed in heavy brackets [1 appears inthe original patent but forms no part of this reissue specification;matter printed in italics indicates the additions made by reissue.

This invention relates to valve constructions for controlling the flowof fluid, and is particularly adapted to the control of high temperaturehigh pressure gaseous fluids such as steam.

This application is a continuation in part of my earlier filedapplication for "Valve Constructions, Serial No. 596,382 filed June 7,1945, now Patent No. 2,621,015, wherein are disclosed certainimprovements in valve body construction which reduce the resistance tothe flow of the fluid through the valve body. Included in myimprovements are the shaping of the valve closure member or disc guidingribs so that they assist in directing the fluid flow and olfer lessresistance thereto, and an improved relation of the valve seat withrespect to the valve inlet and outlet passages, and improvedstreamlining of the interior of the valve body and interior partstherein so that the fluid in its passage from the inlet to the outletmeets with a minimumof resistance. This reduction in resistance to flowresults in important savings in costs because of the decrease in powerlosses. Such ower losses are considerable particularly when the v vesare used in steam power plants to control the flow of high pressure andV high temperature steam flowing at high velocities.

I have provided an improved valve body wherein the inner surfaces aresmoothly profiled and changes in shape are provided for accommodation ofthe valve disc and stem with no obstructions causing abrupt changes inthe direction of flow of the fluid. The valve closure member or disc isof a new cross-section which presents a minimum of resistance to thefluid and aids in directing it towards the outlet of the valve body.Novel and improved means for preventing eddying and the like at the borefor the stern are also provided. As a result of the foregoingimprovements I provide a valve of greatly improved performance.

It is therefore a primary object of my invention to provide an improvedvalve body which presents a minimum of interference or resistance to thepassage of fluid therethrough. While the invention is illustrated as aplied to an angle type non-return valve, it is to be un erstood that thistype is used forillustrative urposes only, and that the novel rinciplesof m'irinvenuon are equally applicable to glo or straightough valves tovalves in general wherein a closure disc or the like is rovided in the epath of the fluid flow.

Another important object of my invention is the provision of an improvedvalve body having an enlarged portion accommodating a valve disc or thelike wherein the interior of the body and the parts therein are so sha das to direct the fluid from the inlet to the outlet wi a minimum ofresistance and eddy currents.

Another object is the provision of an improved valve body having aninlet and an outlet connected by smoothly tapering interior walls withan enlarged portion which houses the valve disc or the like.

Still another object of my invention is the provision of an improvedvalve body having an inlet and an outlet and an enlarged portion housinga valve disc or the like, wherein the valve disc offers a minimum ofresistance to fluid flow when unseated, and provided with e interior ofthe body being so shaped as to guide VIII-VIII of Figure 1; and

the fluid with minimized interference from the inlet to the outlet.

Other objects will become apparent as the description proceeds inconnection with the accompanying drawings, wherein:

Figure 1 is a vertical central sectional view of an angle valveillustrating an embodiment of my invention.

Figure 2 is a section along line Il--II of Figure 1.

Figure 3 is a sectional view of the valve body along line III-III ofFigure 1, the valve disc, piston and stem being omitted. I

Figure 4 is a view in side elevation of one of the curved guiding ribsas viewed from a position indicated by line I \I',IV of Figure 3, andshowing the curvature of the r1 s.

Figure 5 is a sectional view substantially along the line V--V of Figure1.

Figure 6 is a sectional view substantially along the line VI-VI ofFigure l.

Figure 7 is a sectional view substantially along the line VII-VII ofFigure 1.

Figure 8 is a sectional view substantially along the line Figure 9 is asectional view of the valve body of Figure 1 combined with asuperimposed phantom view of an old style valve body for the same pipesize to illustrate the diiferences in valve seat arrangement and metaldistribution.

As shown in Figure 1, a valve body 1 of the angle type has an inlet 2and an outlet 3 substantially at degrees from the inlet. Coaxial withthe inlet 2 the body has a tubular extension 4 wherein is located abonnet 5 having a central passage for a valve stem 6. A yoke 7 is seatedupon and clamped to the top of the extension 4 by lock rings 8 and 9which engage parallel exterior grooves in the body and yoke. A yokebushing 10 is rotatably journalled in beanngs in the top of the yoke 7and is internally threaded for engagement with the top of the valve stem6. An impactor type handwheel 11 is journalled for rotation on a bushing12 which is fastened to a cross arm 13 keyed to the yoke bushing 10 sothat when the handwheel is spun, internal projections 14 thereon willstrike the arms of the cross arm 13 to rotate the yoke bushing 10 andraise or lower the valve stem 6. A guide collar 15 is fastened to thestem 6 and extends through an opening 16 in the yoke, thus preventingrotation of the valve stem.

The upper end of the valve stem is thus guided by the yoke. The bonnet 5provides a second guide means for the valve stem, having bearings 17 and18 for this urggsj. That part of the stem 6 which passes through c ings17 and 18 is slightly reduced in diameter, thus forming a shoulder 18aon the stem, which when the stem is in the full raised position engagesa coned portion on the bottom of the bearing 18 and seals off thepassage in the bonnet 5 against the pressure of the fluid in the valvebody 1. Packing 19 in the bonnet is compressed by a gland 20 to insureagainst leakage of fluid around the valve stem since the shoulder 18a isineffective as a seal unless the valve is fully open. A sealing gasket21 is comressed between a shoulder on the bonnet and a retainer 22 whichis threaded into the top of the extension 4 on the valve body 1, thebonnet being drawn against the gasket and retainer by means of nuts 23on top of a bonnet retainer ring 24, as well as by the fluid pressureinside the valve body 1.

That part of the described structure from the bonnet 5 upwards andincluding the bonnet sealing means etc. does not form any part of thisinvention but is claimed and more completely described in my copendingapplication for Valve Construction filed April 15, 1946, Serial No.662,341 now Patent No. 2,665,875.

As previously stated, the instant invention relates to improvements inthe valve'body 1 whereby the fluid is allowed to pass from the inlet 2to the outlet 3 with a minimum of interference and resistance.

As shown in Figure 1, an annular seat member 25 having an inwardlytapering profile is located within the body 1 adjacent the upper end ofthe inlet 2 to provide a valve seat for a valve closure member or disc26. Member 25 may be secured by a weld 27 as shown, which is fair-edinto the profile of member 25 so as to present a smooth slightlyconstricted inlet to the valve body which will cause a slight increasein velocity 'of the fluid as it asses into that part of the valve bodyoccupied by the c osure member 26.

In Figure 1 the closure member 26 is shown seated and in phantom view itis shown in its raised or full open position at 26a. Also, as shown inFigure l. the upper surface 26c and the lower surface 26b of the closuremember 26 which are exposed to-the fluid flow when the valve is open,are of rounded streamlined spherical shape and the closure member invertical cross section is somewhat elliptical so as to aid, with aminimum of resistance, in directing the flow of fluid in its passagefrom the inlet 2 to the outlet 3 both above and below the closure member26. Valve closure member 26 is also provided with a slight peripheralrecess adjacent its lower surface 26c to provide a conical shoulder 28which bears against a mating portion or seat on the annular member whenthe valve is closed. Welded to and extending upwardly from the closuremember 26 is a hollow tubular valve stem 29 provided with a vent 30adjacent the valve closure member, the bottom of the stem 6 beingslidable within the hollow stem 29 to control the position of valveclosure member or disc 26 by contact with a bearing surface 31 in theclosure member 26. Fixedly attached by welding to the upper end ofhollow stem 29 is an enlarged piston formed by a head and a skirt 33having piston rings 34 adjacent its upper end. An inner wall 32 alsoconnects the piston skirt 33 to the hollow stem 29. Skirt 33 has asliding fit within the bore 36 of the tubular extension 4 of the valvebody. The piston has a dashpot action within said bore, being forcedupwardly against the bottom of the bonnet 5 by fluid pressure within thevalve body when the valve closure member 26 is fully raised from itsseat. When so raised, the wall 32 blocks off the bore 36 therebyavoiding formation of a pocket, and providing a substantially smoothcontinuation of the inner surface of the valve body thus minimizingturbulence of fluid flow and preventing eddy currents and energy loss inthis section of the valve body. When valve closure member 26 is notfully raised the lower end of the piston will project into the hollowspace in the valve body, as will be apparent, since it is rigid andmoves with the valve closure member. However, even when the closuremember 26 is not fully open, the piston causes less disturbance to fluidflow than would be caused by the cavity of the bore 36. In my saidparent application Serial Number 596,382 I disclose a series of spaceddiscs on the piston 29 which provide closures for the bottom of bore 36when the valve is not fully open.

In valves of the type described herein it has been common practice inthe past to have straight ribs extending from the inner wall of thevalve body towards the valve disc to guide the valve disc axially in itsmovement toward and from its seat. Such ribs insure the correct guidanceof the disc so that it will engage its seat properly and provide aproper closure therewith. Such ribs are necessarily located in the pathof flow of the fluid through the valve body, and they are open to theobjection that they impede the flow of fluid through the valve andcreate turbulence eddy currents and energy losses.

In the illustrated embodiment of my invention I employ four guide ribsspaced substantially 90 degrees apart as best shown in Figure 3. Two ofthese ribs 37 and 39 lie substantially in the common vertical plane ofthe axes of the inlet 2 and outlet 3 and are contoured to avoid impedingthe fluid flow. The other two ribs 38 and 40 are curved in the directionof fluid flow, the curvature of rib 40 being shown in elevation inFigures 1 and 4. As clearly shown in Figure 4 these ribs curve towardthe outlet 3 more rapidly at their upper portions than at their lowerportions. Rib 38 is similarly curved in the same direction, as will beunderstood. The inner edges of the ribs 37 to 40 provide guidingsurfaces with which the valve disc 26 has a sliding engagementthroughout its opening and closing movements to assure that it remainsin alignment with its seat. Preferably, the inner edges of the ribs aremachined so that they form portions of a cylinder. That part of rib 40which forms one of said cylindrical portions is indicated by thereference number 41 in valve seat and extend nearly half way toward thebore 36 as shown in Figure I, so that they are still engaged u 4 by thevalve disc when it is in its full open cated at 26a.

As previously described, the cross-sectional area through which thefluid flow passes is nearly constant beyond the constriction formed bythe annular member 25, so that in the case of gaseous fluids there willbe substantially no expansion or compression thereof in the valve body,although I prefer that the cross-sectional passage area around the valvedisc in its open position be somewhat greater than the passage areas inthe inlet 2- and outlet 3. In order to provide suflicient interior spacewithin the valve body for passage of the fluid and to permit suchpassage with a mimimum of losses, the valve body is enlarged in theregion surrounding the valve disc 26 in its full open position. Thisenlarged interior cross-sectional area occurs in the plane of thesection of Figure 1 as well as in the section of Figure 3. As shown inFigure l the interior of the valve body tapers inwardly more rapidlyabove the line III-III than below that line, so that the fluid isdirected smoothly towards the section indicated by the line VV into theoutlet portion of the valve body.

The sections shown in Figures 3 and 5 to 8 show how the cross-sectionalarea of the fluid passageway through the interior of the valve bodygradually changes from a wide passageway of relatively short height tothe nearly circular passageway in the approach to the end of the outlet3 where the cross-section is a true circle. Each of Figures 6, 7 and 8has imposed thereon a dot dash circle 43 which represents the circularcross section of the valve outlet 3 at a point indicated by line 4343 ofFigure 1. These circles 43 offer a comparison of the true sections atthese points with the circular section at the end of the outlet 3.Preferably the area of the passage around the valve disc in openposition is somewhat greater than the passage areas in the inlet 2 andthe outlet 3. This provides a gradually tapering passageway from theenlarged portion around the position of the fully raised valve disc tothe circular section 43 adjacent the egress end of outlet 3. Theinterior of the enlarged portion of the body surrounding the valve disc26 is of an inverted pearshaped cross section with thestem portionextending downward to the upper end of the annular seat member 25, aswill be seen by the outline of the interior surface indicated by thevreference numerals 44 in Figure 1. Also, in the section of Figure 3 theinterior is somewhat pear-shaped although the transverse sections in theoutlet 3 change from elliptical to circular as the egress end of outlet3 is approached. For purposes of an illustrative example only, Figures 3and 5 to 7 show the dimensions of the interior of a preferred design ofvalve body embodying my invention, of such size that the circular inlet2 and egress end of outlet 3 have interior diameters of 10% inches.

Seat 25 and ribs 38 and 40 are so located, and ribs 38 and 40 are socurved, and the interior of the valve body is so shaped thatapproximately two-thirds of the volume of fluid flow through the bodypasses between the ribs 38 and 40 and raised valve disc 26 in full openposition directly into the outlet of the valve body while the remainingone-third will pass around the edges of the valve disc and be directedto the outlet 3 by the inner walls of the valve body and by the pistonhead 32 which closes the bore 36. The rounded and streamlined upper andlower surfaces of the valve disc ofler very much less resistance to thepassage of the fluid that passes around the disc and over the surfacesthereof than do the former type of valve discs one of which is shown at42 in the dotted line phantom view of Figure 9.

In Figure 9 is shown in solid lines the valve body, curved ribs and discetc. constructed in accordance with my invention as described above.Superimposed over my improved valve is a phantom view in dotted lines ofthe prior valve body of a like size designated by the reference number49. In this former style body the inlet 50 and outlet 51 join thecentral body section more abruptly as shown, and their interiorcross-sections are circular. The valve disc 42 is of heavierconstruction than my improved valve disc 26 and is provided withirregular surfaces which cause extreme turbulence of the fluid passingaround the valve. The valve seat 53 is seated in an internal shoulderwhich projects abruptly into the path of the fluid flow and lies well upin the enlarged portion of the valve body 49 just below the axis of theoutlet 51. The valve disc guide ribs (only one of position indiwhich isshown at 54) are all parallel to the valve stem shows how the loweringof the valve seat well below the' axis of the outlet 3 and substantiallyat the intersection of the inlet 2 with the enlarged portion of the body1 permits the fluid to change direction in a gradual curve rather thanabruptly as it does in the old style valve body where the valve seat 53is in a much higher relative position.

The invention may be embodied in. other specific forms without departingfrom the spirit or essential characteristics thereof. Thepresentembodiment is therefore to be considered in all respects as illustrativeand not restrictive, the scope of the invention being indicated by theappended claims rather than by foregoing description, and all changeswhich come within the meaning and range of equivalency of the claims aretherefore intended to be embraced therein.

What is claimed and desired to be secured by United States LettersPatent is:

1. A valve construction comprising a hollow body having an inletandoutlet connected to an enlarged portion, all having axes lying in oneplane, said outlet having a curved axis in said plane whereby the changein direction of fluid flow occurs partly in said outlet, said enlargedportion providing a housing for a valve closure member operable to coactwith a seat to control the fluid flow, the cross section of said outletadjacent said enlarged portion being substantially of the same shape andsize as the cross section of said enlarged portion at their intersectionand the inner walls of said enlarged portion and'outlet merging in asmooth continuous surface devoid of rapid changes in direction, theinternal cross sectional section of said outlet changing from asubstantially elliptical shape where it joins said enlarged portion to acircular section at the end thereof.

a 2. The valve construction described in claim 1 wherein said enlargedportion is provided with inwardly extending ribs curved toward saidoutlet to direct the fluid v flow thereto. I Y

3. The valve construction described in claim 1 wherein said enlargedportion is provided with inwardly extending ribs curved toward saidoutlet to direct fluid flow therethrough, the inner edges of said ribsforming spaced portions of a cylindrical surface for guiding a valveclosure member substantially coaxially with said inlet.

. 4. The valve construction described in claim 1 wherein said enlargedportion is provided with inwardly extending ribs from a point adjacentsaid inlet to approximately the largest part of said enlarged portion,said ribs being curved toward said outlet to direct the fluid flowthereto, the curvature of said ribs being smaller adjacent said inletthan at their other ends.

5. The valve construction described in claim 1 wherein a seat for avalve closure member is provided substantially at the juncture of theenlarged portion of said hollow body with said inlet.

6. A valve construction comprising a hollow body having an inlet and anoutlet connected to an enlarged portion, all having axes lying in oneplane, said outlet having a curved axis in said plane whereby the changein direction of fluid flow occurs partly in said outlet, the crosssection of said outlet adjacent said enlarged portion beingsubstantially of the same shape and size as the cross section of saidenlarged portion at their intersection and the inner walls of saidenlarged portion and outlet merging in a smooth continuous surfacedevoid of rapid changes in direction, the internal cross sectionalsection of said outlet changing from a substantially elliptical shapewhere it joins said enlarged portion to a circular section at the endthereof; means forming a valve seat substantially at the juncture ofsaid enlarged portion of said hollow body with said inlet; a valveclosure member in said enlarged portion, movable away from said seat toa raised position, and towards said seat for engagement therewith toprovide a closure; and inwardly extending ribs in said enlarged portion,said ribs being curved toward said outlet to direct flowing fluidthereto, the inner edges of said ribs forming spaced portions of acylindrical surface for guiding said valve closure memberperpendicularly to said valve seat.

7-. A valve comprising a hollow body having an inlet and an outlet, saidinlet and outlet being connected by; an enlarged portion; a valveseatadjacent the juncture of said inlet and said enlarged portion and atan angle to said outlet, a valve closure member in said enlarged 'tionand towards said seat to provide a closure therewith;

and inwardly extending ribs in said enlarged portion, said ribs beingcurved toward said outlet to direct flowing fluid thereto, the inneredges of said ribs forming spaced portions of a cylindrical surface forguiding said valve closure member perpendicularly to said valve seat.

8. A valve construction comprising a hollow body and angularly relatedinlet and outlet portions communicating therewith, the cross section ofsaid outlet portion adjacent said.body being-of substantially the sameshape and .size as that of said body at their intersection,. the innersurfaces of said bodyand said outlet having changing merging curvatures;a valve seat normal to the axis of said inlet portion adjacent theentrance from said inlet to said body; said body having a bore oppositeto and substantially coaxial with said inlet portion and normal to saidvalve seat; a valve closure member having upper and lower smooth convexflow directing surfaces wholly within said body movable away from saidseat to a raised position and toward said seat to provide a closurethere with, the cross-sectional area of the passageway through said bodybeing greater in the region adjacent the raised position of said closurethan in either of said inlet or outlet portions; and means attached toand spaced from said valve closure member operable to provide a smoothcontinuous inner surface at the entrance to said bore when the valveclosure member is fully raised but projecting into said body when thevalve closure member is only partly raised so that fluid may flowthrough said body with a minimum of disturbance.

9. A valve construction comprising a hollow body having angularlyrelated inlet and outlet portions, a valve seat within said bodyadjacent said inlet portion, a valve closure member movable within saidhollow body toward and away from said valve seat to control fluidcommunication between said inlet and outlet portions, and a plurality ofcurved guide means for said closure member formed integrally with saidhollow body having a first portion substantially parallel to the axis ofsaid inlet portion and having a second portion angularly inclined withrespect to said first portion in the direction of fluid flow to directfluid through said hollow body toward said outlet portion.

10. A valve construction according to claim 1 in which said enlargedportion is formed with a plurality of inwardly extendingcircumferentially spaced ribs, at least one of said ribs being flat andbeing disposed in said one plane, and two of said ribs being disposed atopposite sides of said enlarged portion and curved toward said outlet todirect fluid flow thereto.

11. A valve construction according to claim 10 in which the inner edgesof said ribs form spaced portions of a cylindrical surface eo-axial withsaid inlet to guide said valve closure member for movement toward andaway from said seat.

12. A valve comprising a body having an inlet passage, an outlet passagedisposed at an angle to said inlet passage, and a connecting passagebetween said inlet and outlet passages, a valve seat at the juncture ofsaid inlet and connecting passages, a valve member axially mavable toand from said valve seat, said member comprising a disk having a flowdiverting surface opposed to the valve seat, and flow directing vanesinternally formed on the wall of said connecting passage intersectingsaid surface of said valve member in its open position andcircumferentially spaced about said valve seat, said vanes extendingfrom said valve seat for the major part of the distance to a planeparallel to said seat "and containing the axis of said outlet passage,said plane being above the level of said surface of said valve member,and having a linear curvature from said seat toward the ingress end ofsaid outlet passage presenting concave flow directing surfaces to thefluid stream and cooperating with said flow diverting surface of saidvalve member when in open position to directly discharge the fluidpassage into said outlet passage.

. 13. A valve construction as defined in claim 12 whereinthe peripheryof said valve member is substantially tangent to the ingress end of saidoutlet passage.

14. The valve construction as defined in claim 12, wherein the inneredges of said vanes define segments of a cylindrical surface guidablycontrolling axial movement of the valve member.

15. A valve comprising a body having inlet and outlet passages and'aconnecting passage between its inlet and outlet passages that issmoothly curved and sfree from abrupt change of direction and free fromback-pressure producing obstruction, said valve body having a valve seatbetween said inlet and connecting passages of an inner diametergradually constricted in the direction of fluid flow therethroughwhereby the velocity of flow through said connecting passage issubstantially greater than the velocity of the flow of said fluid insaid inlet passage, a valve disk movable axially from and towards saidvalve seat, a dash pot structure carried by said valve body including acylindrical bore opening into said connecting passage and a piston insaid cylindrical bore and a rigid member connecting said piston withsaid valve disk, closure means secured to and movable with said valvedisk and closing the inner end of said cylindrical bore when said valvedisk is in its fully opened position and thereby smoothly continuing thesurface of said connecting passage at the inner end of said cylindricalbore, and flow directing ribs carried by said valve body and extendinginto said connecting passage, said ribs having surfaces conformed toengage fluid flowing in said connecting passage and to discharge saidfluid in the direction of flow through said connecting passage.

16. A valve comprising a body having inlet and outlet passages and aconnecting passage between its inlet and outlet passages that issmoothly curved and free from abrupt change of direction and free fromback-pressure producing obstruction, said valve body having a valve seatbetween said inlet and connecting passages of an inner diametergradually constricted in the direction of fluid flow therethroughwhereby the velocity of flow through said connecting passage issubstantially greater than the velocity of the flow of said fluid insaid inlet passage, a

'valve disk movable axially from and towards said valve seat, a dash potstructure carried by said valve body including a cylindrical boreopening into said connecting passage and a piston in said cylindricalbore and a rigid member connecting said piston with said valve disk,closure means secured to and movable with said valve disk and closingthe inner end of said,cylindrical bore when said valve disk is in itsfully opened position and thereby sage, and each of said second ribshaving a curved surface engaging fluid flowing in said connectingpassage and changing the direction of flow of said engaged fluid anddischarging the same in the direction of fluid flow through saidconnecting passage.

18. A valve comprising a body having inlet and outi let passages and aconnecting passage between said inlet smoothly continuing the surface ofsaid connecting pas- 1 sage at the inner end of said cylindrical bore,and flow directing ribs carried by said valve body and extending intosaid connecting passage, said ribs having surfaces conformed to engagefluid flowing in said connecting passage and to discharge said fluid inthe direction of flow through said connecting passage, said ribs havingedge surfaces adjacent said valve disk and constituting guiding ribs forsaid valve disk.

17. A valve comprising a body having inlet and outlet passages and aconnecting passage between said inlet and outlet passages that issmoothly curved and free from abrupt change of direction and free fromback-pressure producing obstruction, said valve body having a valve seatbetween said inlet and connecting passages of an inner diametergradually constricted in the direction of flow therethrough whereby thevelocity of flow through said connecting passage is substantiallygreater than the velocity of flow of said fluid in said inlet passage,avalve disk movable axially from and towards said valve seat, a dash potstructure carried by said valve body and including a cylindrical boreopening into said connecting passage and a piston in said cylindricalbore and rigidly connected with said valve disk, closure means securedto and movable with said valve disk and closing the inner end of saidcylindrical bore when said valve disk is in its fully opened positionand thereby smoothly continuing the surface of said connecting passageat the inner end of said cylindrical bore, a first and straight ribcarried by said valve body and extending into said connecting passage inthe plane of flow in said connecting passage, and second and curved ribscarried by said valve body and extending into opposite sides of saidconnecting pas,-

and outlet passages that is smoothly curved and free from abrupt changeof direction and free from backpressure producing obstruction, saidvalve body having a valve seat between said inlet and connectingpassages of an inner diameter gradually constricted in the direction offlow therethrough whereby the velocity of flow through said connectingpassage is substantially greater than the velocity of flow of said fluidin said inlet passage, a valve disk movable axially from and towardssaid valve seat, a dash pot structure carried by said valve body andincluding a cylindrical bore opening into said connecting passage and apiston in said cylindrical bore and rigidly connected with said valvedisk, closure means secured to and movable with said valve disk andclosing the inner end of said cylindrical bore when said valve disk isin its fully opened position and thereby smoothly continuing the surfaceof said connecting passage at the inner end of said cylindrical bore, afirst and straight rib carried by said valve body and extending intosaid connecting passage in the plane of flow in said connecting passage,and second and curved ribs carried by said valve body and extending intoopposite sides of said connecting passage, and each of said second ribshaving a curved surface engaging fluid flowing in said connectingpassage and changing the direction of flow of said engaged fluid anddischarging the same in the direction of fluid flow through saidconnecting passage, all of said ribs having edge surfaces adjacentsaidvalve disk and constituting guidings ribs for said valve disk.

19. In a valve construction, a valve body having inlet and outletpassages and a connecting passage between said inlet and outletpassages; a valve seat between said inlet passage and said connectingpassage; a valve disk movable axially from and towards said valve seat;a bore in said valve body coaxial with said valve seat; said bore beinglarge enough for passage of said valve disk therethrough duringassembly; first guide means for said valve disk comprising an elementslidably mounted in said bore, and means rigidly connecting said elementand said valve disk, said' means being smaller in diameter than saidvalve disk or element; second guide means for said valve disk comprisinga series of spaced fixed vanes in said connecting passages, extendingtowards the axis of said valve disk and their inner edges providingsegments of a cylindricalsurface for guiding the valve disk in itsmovements, said vanes being curved in the direction of fluid flow fromsaid valve seat to said outlet passage; and closure means carried by themeans connecting the valve disk and slidably mounted element, saidclosure means being operable to close the end of said bore facing thevalve disk when the valve disk is raised from its seat.

20. The valve construction described in claim I, including meansdefining a valve seat adjacent said outlet portion anda rib extendingfrom a point adjacent said seat into said outlet substantially centrallyof said outlet, said rib extending at least to the end of the openingstroke of said closure member and having a surface forming a guide andsupport surface for said closure member during its movement.

References Cited in the file of this patent

